Constrained gamma-Z interference corrections to parity-violating electron scattering

TL;DR

This paper refines the gamma-Z interference correction estimates for parity-violating electron scattering, reducing uncertainties and enabling more precise tests of the Standard Model through improved theoretical predictions.

Contribution

It provides a comprehensive analysis combining existing models and new data, significantly reducing uncertainties in gamma-Z interference corrections for the proton's weak charge.

Findings

Gamma-Z box correction at Qweak kinematics: (5.57 +- 0.36) x 10^{-3}

Reduced uncertainties in gamma-Z interference corrections

Enhanced predictions for parity-violating deep-inelastic asymmetries

Abstract

We present a comprehensive analysis of gamma-Z interference corrections to the weak charge of the proton measured in parity-violating electron scattering, including a survey of existing models and a critical analysis of their uncertainties. Constraints from parton distributions in the deep-inelastic region, together with new data on parity-violating electron scattering in the resonance region, result in significantly smaller uncertainties on the corrections compared to previous estimates. At the kinematics of the Qweak experiment, we determine the gamma-Z box correction to be ReBox^V_{gamma-Z} = (5.57 +- 0.36) x 10^{-3}. The new constraints also allow precise predictions to be made for parity-violating deep-inelastic asymmetries on the deuteron.